Surgical Indications and Decision Making

Abstract

Rupture of intracranial saccular aneurysms is the most frequent cause of subarachnoid hemorrhage (SAH). When conservatively treated, about 70% of the cases with ruptured aneurysms eventually die (Locksley 1966). The contention by some neurologists that conservative treatments are better than any surgical treatment is untenable. The three major causes of death in SAH patients are 1. direct effects of subarachnoid bleeding, 2. rebleeding of aneurysms, and 3. cerebral vasospasm, or cerebral arterial spasm, which may later develop in 40–60% of the cases (Odom 1975, Saito and Sano 1980) and may lead to cerebral infarction. According to the recent International Cooperative Study on timing of aneurysm surgery (Kassell and Torner 1984), vasospasm (33.5%), direct effects of SAH (25.5%), and rebleeding of aneurysms (17.3%) were important causes of disability and death in 1.272 patients. Direct effects of SAH or acute ischemic neurdogical deficits (AINDs) of the previous chapter involve the general condition of patients which can be expressed as grades (Botterell et al. 1956, Hunt and Kosnik 1974). Both the general condition and cerebral vasospasm are dependent upon the amount and distribution of subarachnoid blood (Fisher et al. 1980, Sano 1983). The same is true for both acute and chronic hydrocephalus after SAH (Black 1986). Furthermore, the sites of aneurysms and their rupture (e.g., the brain stem), increased intra-cranial pressure due to acute brain swelling (its cause being in dispute) or acute hydrocephalus, and intracerebral hematomas, all of which should affect the grades, will hold sway over the outcome of the patient. Other incidental pathological conditions, such as diabetes mellitus, atherosclerosis, etc. and the age of the patient may have an influence upon the mortality and morbidity.